Fruit Tree Insects

FRUIT TREE INSECT PESTS

Several important insect pests affect fruit grown in the home garden. Good quality, satisfactory fruit cannot be grown without good pest control and tree care. If you wish to grow your own fruit, you must be willing to learn the important pests and the methods to control them and then be willing to expend the time and effort to do the job right. This information will help you to understand the main pests that affect fruit trees and the methods to produce good quality fruit.

Before fruit trees are planted, home fruit growers should be aware of the time and work they entail and must be willing to care for them properly. The following cultural methods will reduce many pest problems without using pesticides. Sanitation includes pruning and cleaning up twigs and branches and fruit that drops to the ground unused. Proper irrigation and fertilization maintain tree health and reduce stress. Good weed control beneath fruit trees reduces habitat for cutworms and other pests. Plant varieties that are suitable to your growing area.

Click on thumbnail to see larger view.

  Coddling moth damage

The coddling moth or common apple worm is the most important pest of apples. It also attacks pears. This type of damage is very familiar to anyone with backyard trees.

  Coddling moth adult

Adult moths first emerge in May followed by a second generation and occasionally a third as the summer progresses. After mating, the female moth lays eggs on the developing fruit.

  Codling moth larva

Eggs hatch in one to two weeks and tiny larvae burrow into the apple immediately, usually around the calyx end.

  Internal apple damage by codling moth

The larva feeds as it bores into the center of the apple where it feeds on the seeds and core. As it matures, it tunnels back out and leaves the fruit to develop to the adult stage.

  Rosy apple aphid

Rosy apple aphids are serious pests on apples in some years. It is one of two important aphid pests of apples.

  Rosy apple aphid eggs

Eggs of rosy apple aphids are laid on apple twigs and branches in late fall.

  Early rosy apple aphids

Newly hatched aphids are found on early bud growth in the spring. They are dark green when young but become a rosy brown color as they mature.

  Rosy apple aphid damage

Early season rosy apple aphid feeding causes leaf curling and misshapen and dwarfed fruit. These aphids are usually only found on apples early in the season then they move to weed hosts by early summer.

  Apple aphid colony

The apple aphid also overwinters as an egg on tree bark but hatches later in the spring and develops large colonies in early summer. With heavy infestations, the apple aphid retards the growth of new shoots. Apples and leaves become covered with large quantities of honeydew followed by a sooty mold.

  San Jose scale on fruit

San Jose scale is a serious pest of neglected fruit trees. Unless controlled, this insect may result in heavy infestations on apple trees that can kill entire limbs. Here the scale is seen on the fruit.

  San Jose scale adult and crawlers

San Jose scales live under this cover and eventually lay eggs. The eggs hatch into the crawler stage by mid-summer. The tiny orange crawlers are visible here next to the scale.

  Oyster shell scale

Oyster shell scale is another pest of apples and other fruit that may kill trees if neglected.

  White apple leafhopper

White apple leafhoppers have been an increasingly important pest in commercial orchards but seldom are of concern to the backyard tree owner.

  Tentiform leafminer adult

Tentiform leafminer is an incidental pest on backyard apple trees. The developing larva burrows into the leaf causing death to portions of the leaf.

  Pandemis leafroller damage

Pandemis leafroller has multiple generations in a season, all of which can cause damage to fruit and leaves.

  European red mite

European red mites are a serious problem to backyard fruit tree owners in years when extended periods of hot, dry weather occur or when trees become weakened through poor water management or other poor management practices.

  McDaniel mite and predatory mite

McDaniel mites (larger mite) may also occur in backyard fruit trees. As with the European red mites, these mites are normally held in check by predatory mites. Predatory mites are smaller than the harmful species. They are pear shaped and usually light in color.

  Pear Psylla

Pear psylla is a pest only of pears. It is an early season, cool weather pest. Pear psylla weaken the tree and also deposit a sticky honeydew that causes russeting on the pears.

  Peach twig borer damage to peach

The peach twig borer causes the same type of damage in stone fruits that the codling moth does in apples. The end result is wormy fruit.

  Peach twig borer adult

The twig borer is a small moth in the adult stage. It emerges in June, mates, and lays eggs on developing fruit. Two generations are normal for Idaho with the last overwintering as a small larva in a cocoon-like hibernaculum on small branches. As the weather warms in the spring, the larvae bore into new terminal growth causing it to die, hence the name twig borer. Peaches, apricots, plums, and the nectarines are affected by this pest.

  Peach tree borer

Peach tree borer is another pest that affects the stone fruits. The adult is a blue clear-winged moth that emerges in late-June and early July.

Peach twig borer damage

Peach twig borer damage occurs as the developing larvae burrow and feed beneath the bark through the fall and winter. Young trees may be killed by one larva, although older trees may survive with several for a time.

  European earwig

The European earwig is an occasional pest on fruit trees but seldom causes any serious damage. It is a nuisance pest. Earwigs tend to be found on ripe fruit and sometimes enter split or overripe peaches, apricots, and nectarines.

  Cherry fruit fly

Cherry fruit fly is a pest of cherries only. The adult fly is about the same size as an ordinary house fly, but it has distinctive markings on the wings. They emerge in late May and begin to lay eggs in nearly ripe cherries.

  Cherry fruit fly damage

When the eggs hatch, the tiny maggots feed inside the cherries causing decay of the fruit.